Chemical composition, <i>in vitro</i> antiparasitic, antimicrobial and antioxidant activities of <i>Frankenia thymifolia</i> Desf.

This study was performed on the derived fractions [chloroform (FT-C), ethyl acetate (FT-E) and n-butanol (FT-B)] of the 70% ethanol extract prepared from Frankenia thymifolia, endemic to North Africa. The fractions showed high total phenolic and flavonoid contents particularly FT-E. These results agreed with their antioxidant effects. Indeed, all the fractions were able to scavenge 1,1-diphenyl-2-picrylhydrazyl radical, with a better power of FT-E. These results were supported by the inhibition of β-carotene oxidation assay. The fractions showed moderate activity against Acanthamoeba castellanii and Leishmania amazonensis with a better activity of FT-E against A. castellanii. Moreover, FT-B exhibited an interesting antimicrobial activity against all tested bacteria. The phytochemical investigation of the most active fractions (FT-E and FT-B) led to the isolation and structural determination of six compounds. The observed biological activities may be associated with the presence of quercetin and its derivatives found in the chemical composition of these fractions.</p

Anti-inflammatory and hemostatic effects of <i>Linaria reflexa</i> Desf

The work presented here was aimed to investigate the in vivo anti-inflammatory and in vitro hemostatic activities of Linaria reflexa extract and to establish the relationship between its bioactivity and chemical composition. Twenty-three secondary metabolites were identified, most of them are good anti-inflammatory agents, in line with data by carrageenin-induced rat paw edema assays of the n-butanol extract showing high anti-inflammatory inhibition (63.90%) of edema swelling in the rat paw at the dose 200 mg/kg after 4 h. Furthermore, both extent of inflammatory response and tissue injury were prevented keeping the levels of rate myeloperoxidase (60.16%) and of malondialdehyde, which is the final product of lipid peroxidation generated by free radicals (58.58%). The same extract showed also a remarkable hemostatic effect established by measuring the coagulation time of decalcified plasma (45 s), related to its flavonoid glycosides content.</p

Iridoids and anti-inflammatory properties of <i>n</i>-butanol extract of <i>Linaria tingitana</i> Boiss. & Reut.

<p>The analysis of the <i>n</i>-butanol extract of <i>Linaria tingitana</i> (BELT) by HPLC-DAD–ESI/MS allowed the identification of four iridoids structurally confirmed by NMR and ESI–MS/MS extensive experiments data. The subjection of BELT to the anti-inflammatory activity showed that it exhibited a concentration dependent stabilisation of HRBC membrane, inhibition of protein denaturation and nitric oxide scavenging effect in the <i>in vitro</i> process. These results were confirmed in the <i>in vivo</i> experiments which showed that BELT was found to be most pronounced at 200 mg/kg after carrageenan injection which significantly reduced the swelling in both early and late phases of carrageenan-evoked oedema, as well as a significant reduce at the accumulation of infiltrating cells, inhibition of the myeloperoxidase activity and suppressed the lipid peroxidation. These results were supported by the histological analysis which revealed the reduction of oedema and cells infiltration, this might be influenced by the synergistic action of the above isolated compounds.</p

Glycosyl flavonoid profile, <i>in vivo</i> antidiabetic and <i>in vitro</i> antioxidant properties of <i>Linaria reflexa</i> Desf.

<p>Aerial parts of <i>Linaria reflexa</i>, used in North African folk medicine for treating certain skin diseases, were investigated by HPLC–DAD–ESI/MS technique able to identify the glycosyl flavonoids pectolinarin (<b>1</b>), isolinariin A (<b>2</b>), isolinariin B (<b>3</b>), linariin (<b>4</b>), isolinariin D (<b>5</b>) and isolinariin E (<b>6</b>) as the most abundant components in both hydroalcoholic (HAE) and ultrasound-assisted (UAE) extracts profiles. Metabolite <b>5</b>, isolated and fully characterised by extensive nuclear magnetic resonance (NMR) analysis, has been very recently reported from <i>L. japonica</i> together with the compound <b>6</b>. Good antioxidant activities (DPPH radical scavenging, <i>β</i>-carotene bleaching and reducing power assays) were observed for the extracts. The remarkable antidiabetic activity displayed by UAE (300 mg/kg) has yielded the most marked decrease in blood glucose levels of the alloxan diabetic rats (−72.09%), greater than the effects by the drug glybenclamide (−63.29%). This study reports the first correlation of antidiabetic activity of <i>Linaria</i> sp. extracts with their chemical composition.</p